A severe case of Lemierre Syndrome with Streptococcus constellatus Infection.

A 76-year-old Japanese male presenting with high fever, headache, and disturbance of consciousness was hospitalized. Contrast computed tomography revealed thrombophlebitis in the internal jugular vein and abscesses in the posterior neck region, pharynx, and pterygoid muscle. Streptococcus constellatus infection was confirmed by culture of blood samples, and the patient was diagnosed with Lemierre syndrome. In addition to the administration of antibiotics and anticoagulants, abscess drainage was performed. S. constellatus should be considered as a causative bacterium in elderly patients with Lemierre syndrome.